Abstract
NO induces differentiation and apoptosis in Acute Myelogenous Leukemia (AML) cells. Glutathione S-Transferases (GST) play an important role in multidrug resistance and are upregulated in 90% of AML cells. We have designed a novel prodrug class that releases NO on metabolism by GST. O2-(2,4-Dinitrophenyl) 1-[(4-ethoxycarbonyl)piperazin-1-yl]diazen-1-ium-1,2-diolate (JS-K, a member of this class) has potent antileukemic activity in vitro and in vivo (
Molecular Cancer Therapeutics 2:409-417,2003
). The purpose of this study was to determine the effect of JS-K on angiogenesis. The anti-angiogenic properties of JS-K were tested in 3 different in vitro assays: proliferation, cord formation (reflecting new vessel formation) and migration using Human Umbilical Vein Endothelial Cells (HUVEC). JS-K inhibited the proliferation of HUVEC’s with a 50% inhibitory concentration (IC50) of 0.432, 0.466, and 0.505 μM at 24, 48, and 72 hours, respectively. At concentrations of 1 μM or above, HUVEC proliferation was totally inhibited. In the cord formation assay, treatment with JS-K lad to a decrease in both the number of cord junctions and cord length with an IC50 of 0.637 and 0.696 μM, respectively. At a concentration of 1 μM, JS-K inhibited cord formation completely. JS-K inhibited cell migration at 5 hours using 10 ng/mL VEGF as a chemoattractant. At that time point, migration inhibition occurred at JS-K concentrations that did not affect cell growth with an IC50 of 0.493 μM. We conclude that JS-K is a potent inhibitor of 3 important elements of angiogenesis, namely endothelial cell proliferation, cord formation, and endothelial cell migration. These experiments identify a new mechanism by which JS-K and similar compounds may inhibit leukemia and solid tumor cell growth in vivo. Determining whether the anti-angiogenic effects of JS-K are NO-dependent will require further studies. (NO1-CO-12400).Author notes
Corresponding author
2005, The American Society of Hematology
2004
